Free Shipping on all orders $35 and up.

We offer standard delivery in 3 business days or less.

Please see our shipping map below for estimated times.

Estimated standard delivery time to the U.S. and Puerto Rico

Delivery time estimates do not apply to large or heavy items that require special
shipping (including most TVs), items shipped directly from the manufacturer, or
out-of-stock items. Some items that ship from the manufacturer can only be delivered
to addresses within the 48 contiguous states.

Delivery time for standard shipping to any of the 50 U.S. states or Puerto Rico is 1-3 business days. Saturday, Sunday and national holidays are not considered business days for delivery purposes.

Ask an expert advisor

Keep water out when you run power cable through your car's firewall. The StreetWires FB4 firewall bushing protects your 4-gauge power cable from wear and chafing, and provides a watertight seal when it's tightened down. Lifetime warranty.

Hands-on research

What's in the box?

Threaded bushing shaft

Cap

Nut

Product Research

Features

General
Description: The StreetWires firewall bushing
is a three piece design; the
threaded shaft loads through the firewall, a rounded cap screws on from one side
and a nut from the other. A watertight seal is created as the ends are
tightened. Your wire will be protected from metal jagged edges and moisture.

Available Sizes and Dimensions: The
StreetWiresfirewall bushings are available in three sizes.

8-Gauge Firewall Bushing:

Cut-Out Diameter: 0.58"

Shaft Length: 1.159"

Inner Hole Diameter For Wire:
0.25"

4-Gauge Firewall Bushing:

Cut-Out
Diameter: 0.88"

Shaft Length: 1.275"

Inner Hole Diameter For Wire: 0.5"

1/0 Gauge Firewall Bushing:

Cut Out Diameter: 1.105"

Shaft Length: 1.588"

Inner Hole Diameter for Wire: 0.75"

Our Product Research Team

At Crutchfield, you'll get detailed, accurate information that's hard to
find elsewhere. That's because we have our own in-house Product Research
team. They verify what’s in the box, check the owner's manual, and record
dimensions, features and specs. We stay on top of new products and technologies
to help people make informed choices.

* Agree to Terms
By checking this box you agree your review becomes the property of Crutchfield,
that you are over 18 years of age, that you own or have owned this product, and
that you are located within the United States or its territories. Please see our
Review Guidelines for more information. We reserve the right (but are not
obligated to) review all submissions and edit or remove any review in any manner
which we deem necessary. Your review should be posted within seven days.

It's a Bushing!

I bought this to pass a 4-Gauge power cable through the firewall of my car. I spent several hours dismantling my dashboard trying to find a place to pass this through, or a place to drill. I had no luck with that, but was lucky enough to find an unused, plugged hole in the firewall under the carpet on the passenger side of my car. The bushing didn't fit the hole, but I managed to fit it in the plug that was in the hole! Anyway, the bushing clamped down on the plug and the cable nice and tight. I've no idea how it will hold up over time, but I imagine that if a 1mm thick plastic plug lasted ~20-years that this will outlive the car!

Pros:-Solid
-Fits 4-Gauge Cable

Cons:Does not include a device that magically tells me where I can put a hole in my car's firewall.

Does what it should

Written By Tracy, Sandston, VA. on Thursday, July 08, 2010

I used one of these as I drilled a hole through my firewall to run my 4ga. power lead. I gave it 5 stars because it worked great and I don't need to worry about my power lead running through a jagged hole. Once the wire is run through it the outer cap screws in place and clamps it down so it does not move. Not that this is that big of deal but it does not come with instructions to tell you what size hole to drill. After a quick measurement though I drilled a 3/4" hole, as that was the biggest bit I had but the hole still needed a bit of filing. I'm thinking a 13/16 hole would be perfect.
As usual, Crutchfield is the best!!

Works OK.

This product worked well. I used it to run a 4 guage Rockford wire through the firewall on my Chevy Silverado. It fit OK because the firewall was only 1 layer thick next to the power break booster where I ran the wire.

StreetWires FB4

Written By Anonymous, NC on Tuesday, June 30, 2009

I used this to run a 4 gauge cable through a Cavalier firewall. It worked exactly as I had planned out, and the cable is nice and secure, and waterproof. I used a step drill (unibit) to drill the hole, since no instructions were included I used a caliper to find the size. The Cavalier firewall was only 1 layer thick so the length was perfect.

Professional Solution

I found this to be the professional solution to breaching the firewall to run cable(s). Including instructions in the pack on what size hole to drill and which side or in what order should the bushing be assembled would be helpful to the novice. Otherwise this product really gives a professional look and functionally serves the purpose.

Works Great!

This product worked perfectly for me. It would be nice to have instructions, but the bushing is easy enough to figure out. Once I drilled through my Ford Ranger firewall, the bushing worked just like it was suppose to.

What I liked best was, once I routed my power cable in my engine bay the bushing locks the cable in place with a compression fitting. The threads were somewhat close, but I had a friend hold the engine bay side of the bushing and then I attached my side from inside. By using this bushing instead of a hardware store gromet, you are able to slip the power cable freely to get perfect adjustment and then lock it down, the hardware store gromet forces you to estimate the length, slip it on cable and then force it into your firewall for a snug fit. Pain in your side, I know this bushing saved me much headache.

A good idea...

Written By newfrontier45, Orlando, FL on Monday, October 30, 2006

...but very poorly executed. The threads are just way too short to use on anything but a single layer of thin sheetmetal. I don't know if many firewalls are that thin but the floor of my Chevy 2500HD was way too thick to use this product properly. I was able to utilize it but not in the manner in which it was intended.

A Must-Have Accessory for Amplifier Wiring Install

I installed this product in a 2002 Honda Accord, which has a knockout block in the firewall a little ways above the gas pedal. Upon removing the plastic knockout block I discovered a hole in the neighborhood of 3/4" diameter. I ordered the Streetwires FB4 firewall bushing and was delighted to find it fit.

The firewall bushing serves a few functions:1) It looks great! It gives the install a professional look.2) When the nut is tightened it cinches on the power cord, keeping the cord from sliding in and out and creating a waterproof seal.3) The bushing, of course, keeps the sharp edge of the hole in the firewall from wearing through the power cord installation and causing a short.

My only complaints are that it is impossible to find any information regarding the dimensions of this product online. The product arrived with absolutely no instructions. And, my firewall was a bit too thick for the FB4 and I had to remove the rubber o-ring gasket in order to have sufficient thread space to secure the FB4.

The FB4, although a bit more spendy than a hardware store grommet, is money well spent. It ensures a sharp-looking, worry-free install.